COMET DUO CLASS RULES

1. INTENTION & INTERPRETATION.

1. The intention of the Class Rules shall be to maintain a one-design in which racing is a true test of sailing skill. The boats shall be as alike as possible in all aspects effecting speed and ease of handling. The boat’s characteristics of simplicity, safety, moderate cost and low maintenance shall be maintained,
2. The official language of the Class shall be English. The English text shall prevail in any dispute over translation.
3. In the event of any discrepancy between the rules and the plans, specifications or measurement forms, the rules shall take precedence.
4. The Constitution of the Comet Duo Class Association shall govern the procedure for changes and/or additions to these rules.   
5. The Comet Duo Class Association has now been subsumed into the Combined Comet Class Association, but that has not altered these rules and references to the constitution of the former association remain valid.

2. PROTECTION OF ONE DESIGN.

6. Only AMS Marine and holders of a valid licence from A.M.Simmons shall be entitled to build Comet Duo sailing dinghies.
7. Builders shall be required by their licence to produce boats and parts in accordance with the official plans and specifications issued by the Designer and in accordance with these Class Rules.
8. The GRP hull and deck shall be produced only from official moulds to the standards and specifications of AMS Marine.
9. Any alterations to the hull, deck, spars, or any part of a Comet Duo, except as specified in these rules, and in particular Rule 2.e shall be prohibited.
10. Deviations from the official plans and specifications shall not be permitted, except in respect of the following:-

1. I. deck fittings (see Rule 18.c). 
2. II. tiller extension (see Rule 21).
3. III. sail controls and rigging (see Rule 31). 
4. IV. repairs and painting (see Rule 36).
5. No deviations from the official drawings or specifications permitted by Rule 2.e shall inhibit or impair the facility of mainsail reefing and jib furling. 

3. CERTIFICATE AND REGISTRATION. 

12. Each Comet Duo shall be issued with a sail number when built and recognised only by that number. 
13. A measurement certificate shall be issued with each new Comet Duo in accordance with the Constitution of the Comet Duo Class Association. 
14. No boat shall be allowed to race as a Comet Duo unless it is listed on the Comet Duo Class Association Register and has a Valid Measurement Certificate. 

4. MEASUREMENT. 

15. Only the Class Measurer, the builder, or holder of a valid building license shall be allowed to issue a Measurement Certificate. 
16. Any Comet Duo with a Measurement Certificate shall be liable to be inspected, examined and remeasured at the discretion of the Comet Duo Class Association or its committee. 
17. At the discretion of the approved measurer, the repair and replacement of any part of a Comet Duo may invalidate the certificate of that Comet Duo. 

5. COMPLIANCE WITH RULES. 

1. It shall be the responsibility of the owner to ensure that the Comet Duo complies with the Class Rules. 
2. Any alteration or replacement shall comply with the rules current at the time of the alteration or replacement. 

6. RULING AND DISPENSATIONS.

1. Cases of doubt regarding compliance with the Class Rules shall be referred to the Comet Duo Class Association committee who shall give a ruling. 
2. The Comet Duo Class Association shall be empowered to grant dispensations only in exceptional cases where this is considered to be in the interests of the class. Any such dispensation shall be recorded on the Measurement Certificate of the boat. 

7. MEASUREMENT CONTROLS TERMINOLOGY.

1. The use of the words “maximum” and “minimum” relating to measurements in these rules shall mean that these are the greatest and smallest measurements permitted in each case. 

8. HULL LENGTH AND BEAM MEASUREMENTS. 

1. All length measurements shall be taken from the main aft face of the transom to the extreme front of deck moulding.
2. Length overall. Maximum 3655mm. Minimum 3645mm. 
3. The beam measurement shall be taken at point of maximum beam and be measured to include moulded deck gunnel, but exclude fendering or rubbing strake. 
4. Beam overall. Maximum 1520mm. Minimum 1510mm.

9. MAST POSITION. 

1. The front of the bottom mast hole at a point 10mm up from the base shall be measured from the main aft face of the transom in a straight line parallel to the line of the gunnel and shall be a maximum of 2417mm and a minimum of 2407 (see diagram 1). 
2. The front of top mast location channel at 10mm below deck level shall be measured from the aft face of the transom in a straight line parallel to the line of the gunnel, and shall be a maximum of 2430mm and a minimum of 2420mm. (see diagram 1). 

10. SHROUD POSITION. 

1. The centre of the shroud mounting point shall be measured from a point midway between them and the main aft face of the transom in a straight line parallel to the gunnel, and shall be a maximum of 2085mm and a minimum of 2075mm. (see diagram l). 

11. JIB TACK POSITION.

1. The position of the centre of the jib furling gear mounting point on the bow shall be measured from extreme front of the deck moulding, and shall be a maximum of 70mm and a minimum of 63mm.

12. CENTREBOARD CASE. 

1. Centreboard slot width at 10mm from hull deck surface shall be a maximum of 28mm and a minimum of 26mm. 
2. Centreboard slot width at 10mm from hull deck surface shall be a maximum of 28mm and a minimum of 26mm.
3. The aft end of the centreboard deck slot shall be measured from the main aft face of the transom in a line parallel to the gunnel and shall be a maximum of 1690mm and a minimum of 1680mm. (see diagram l). 
4. The centreboard deck slot length, measured at 10mm from deck surface shall be a maximum of 462mm and a minimum of 452mm. 
5. The forward end of the centreboard hull slot, at 10mm from hull surface, shall be measured from main aft face of transom alongside keelband and shall be a maximum of 2080mm and a minimum of 2070mm. (see diagram l). 
6. The aft end of the centreboard hull slot, at 10mm from hull surface, shall be measured from main aft face of transom alongside keelband and shall be a maximum of 960mm and a minimum of 950mm. (see diagram l). 
7. The centreboard hull slot length, measured at 10mm from hull surface shall be a maximum of 1130mm and a minimum of 1110mm, (see diagram 2). 
8. The centreboard pivot bolt position shall be measured at a right angle from a point 130mm aft of the front end of the centreboard hull slot, and shall be a maximum of 151mm and a minimum of 141mm. (see diagram 2). 
9. The centreboard case height shall be measured from the top of the aft end of the centreboard deck slot vertically square to a point flush with the hull bottom and shall be a maximum of 388mm and a minimum of 378mm. (see diagram 2). 

13. Apertures in the hull skin 

1. Apertures in the hull skin shall not be permitted except those listed in Rule 13. 
2. Centreboard slot. Shall be in accordance with Rule 12. 
3. Self bailer. Maximum number two. Maximum aperture in hull skin 112mm x 50mm.
4. Drain hole in transom. Maximum number one. Maximum diameter of opening 26mm.

14. PROJECTIONS BEYOND HULL SKIN.

1. only permitted projections shall be:- 

1. Rudder fittings and retaining clip.
2. Self bailer, in accordance with Rule 13.c. 
3. III.Drain Plug, in accordance with Rule 13.d. 
4. Keelband, in accordance with rule 16. 
5. Slot gasket fitted between keelband and hull skin. 
6. Deck gunnel noulding and gunnel trim, in accordance with Rule 15. 

15. GUNNEL TRIM. 

1. Wooden, rubber or plastic fendering or rubbing strake permitted fitted to extreme outward edge of deck moulding. 
2. The trim shall be of constant section except for within 40mm of the ends. 
3. Maximum fitted depth of section 26mm. Maximum fitted width 15mm. 
4. Maximum fitted length 3795mm. Minimum length 3785mm. 

16. KEELBAND.

1. Shall be fitted to entire length of keel and stem and shall not be removed. 
2. Maximum width 13mm. Maximum thickness 6mm.

17. APERTURES IN DECKS AND BULKHEADS. 

1. No apertures in decks or bulkheads shall be permitted except those listed rule 17. 
2. Inspection hatches. Shall be of watertight type. Maximum number of three permitted, one in centre of rear seat, one each side of forward bulkhead. Maximum size of their openings shall be 280mm x 180mm.

18. DECK FITTINGS. 

1. No fittings that can be used to control mast, boom, sail or rudder shall be fitted other than the following:- 

1. I.Furling gear and forestay mounting plate. 
2. II.Furling gear control line cleat. 
3. III.Jib sheet tracks. Shall not be moved from standard fitted position. 
4. IV.Two mainsheet horse fittings fitted in standard position on transom top. 

1. Toestrap. A maximum of two toestraps nay be fitted fastening at rear of cockpit floor, centre of forward bulkhead and under centre seat. 
2. Additional deck fittings. The following items or fittings may be fitted: 

1. I.Compasses. 
2. II.Retaining clips or eyes for anchor, warp, and storage bags etc. 
3. III.Rowlock sockets. 
4. IV.Outboard motor mounting pad. 

19. CENTREBOARD. 

1. Only standard centreboard permitted, as supplied by the builder. 
2. Profile. Shall conform to diagram 3. 
3. Pivot bolt position. Shall conform to diagram 3. 
4. Maximum thickness. Maximum 26mm. Minimum 25mm.

20. RUDDERBLADE. 

1. Only standard rudderblade permitted, as supplied by the builder. 
2. Profile. Shall conform to diagram 4. 
3. Maximum thickness. Maximum 26mm. Minimum 24mm.
4. Depth of blade when fitted to boat and in lowered position. Maximum 475mm. Minimum 465mm (see diagram 4).

21 RUDDER STOCK, TILLER AND TILLER EXTENSION. 

1. Shall be of standard type as supplied as original equipment on Comet Duo. 
2. Tiller extension length and type optional. 

22. JIBSTICK. 

1. Maximum length overall 1355mm.

23. HULL WEIGHT. 

1. Condition during weighing:- 

1. All external and internal surfaces shall be dry, to the satisfaction of the Measurer. 
2. II.No fitting shall be weighed with the hull unless it is securely bolted, screwed, bonded or otherwise fixed to the boat as permanent equipment to be carried when racing. Fittings not listed in Rule 14, 18.a, and 18.b shall not be included in the measured weight. 
3. III.The boat shall be weighed with centreboard fitted. 
4. IV.Items excluded from measured weight:- spars, sails, rudder, ropes, rigging, paddle, jibstick and detachable items listed in Rule 18. 

2. Minimum weight. In condition specified in Rule 23,a :- 88kg. 
3. Weight correction. Hulls weighing less than the permitted minimum shall be made up to the permitted minimum by weight correctors of any material, but of a total weight not exceeding 5kg. Weight correctors shall be fitted to the base of the forward bulkhead. 
4. Reduction of weight correctors. Shall not be permitted without an official re-weighing. 
5. Record of weight correction. Weight correctors shall be weighed separately and their weight entered on the Measurement Certificate. 
6. Changing weight. Any permitted alterations to the hull or fittings resulting in a change of weight shall require an official re-weighing. 

24. SPARS. 

1. The mast and boom shall be constructed of the materials required by the official specifications and shall not be altered by cutting, etching sleeving, plugging or drilling except for the attachment of permitted fittings as listed in Rules 25 and 26. 

25. MAST. 

1. Overall length including both end castings shall be 5930+/-5mm. 
2. Mast section to be 55mm x 70mm. AMS Marine design. 
3. Mast fittings. Only the following fittings shall be permitted:- 

1. Mast top casting. 
2. II.Wind indicator or burgee fitting at top of mast. 
3. III.Forestay fitting. Shroud attachment point 4350+/-5mm from mast base. 
4. IV.Sidestay fitting. Shroud attachment point 4300+/-5mm from mast base. 
5. Jib halyard block. Centre of block 4167+/-5mm from mast base. 
6. VI.Gooseneck fitting positioned 875+/-5mm from mast base. 
7. VII.Jib cunninghan lacing eye centre and jib cunninghan/reefing line clamcleat both positioned 815+/-5mm from mast base. 
8. VIII.Mainsail halyard clamcleat centre positioned 670+/-5mm from mast base. 
9. IX.Highfield lever and jibstick eyes centres positioned 562+/-5mm from mast base.
10. Top of kicking strap fitting positioned 135+/-5mm from mast base.

4. Permanently bent masts. Prohibited. 
5. All fittings and rivets shall be of a sealed type to maintain buoyancy of mast. A 5mm drain hole at base of mast is permitted. 
6. Attachments, fittings or devices that may alter the position, rake or height of the mast from the normal designed position, rake or height shall be prohibited.

26. BOOM. 

1. Length including end plugs shall be 2405+/-5mm. Tubing size 51mm x 1.6mm, 
2. Boom fittings. Only the following fittings shall be permitted:- 

1. I.Tack lacing eye at extreme forward end of boom tube. 
2. II.Reefing line clamcleat positioned 90+/-5mm from forward end of boom, 
3. III.Outhaul line jammer positioned 152+/-5mm from forward end of boom. 
4. IV.Front end of the kicking strap fitting positioned 510+/-5mm from forward end of boom. 
5. V.Lacing eye to retain reefing line positioned 1142+/-5mm from forward end of boom. 
6. VI.Reefing line block positioned 235+/-5mm from extreme aft end of boom. 
7. VII.Mainsheet fitting positioned 90+/-5mm from extreme aft end of boom. 
8. VIII.0uthaul block and lacing eye at extreme aft end of boom.

27. STANDING RIGGING. 

1. Sidestays. Length overall between bearing surfaces 3965+/-5mm. Wire diameter 3mm.
2. Forestay. Length overall between bearing surfaces 4008+/-5mm. Wire diameter 3mm. 
3. Shroud adjusters, Multi hole type. Distance between shroud attachment and deck fitting hole centres. Maximum 82mm. Minimum 18mm. 
4. No additional shackles or rigging links etc. shall be fitted. 

28. JIB HALYARD.

1. Shall be of external type, maintaining buoyancy of mast. 
2. Length overall between bearing surfaces 3578+/-5mm. 

29. HIGHFIELD LEVER. 

1. Shall be of standard type as originally fitted. 
2. Jib halyard hook. Length between bearing surfaces, Maximum 55mm. Minimum 45mm.

30. JIB FURLING GEAR. 

1. Jib furling top swivel shall always be fitted, Length between attachment pins. Maximum 33mm. 
2. Jib furling drum shall always be fitted. Length between attachment pins. Maximum 52mm. 

31. RIGGING. 

1. Mainsheet. Aft mainsheet system of 2-1 purchase only. Type and size of blocks and rope shall be optional. 
2. Mainsheet horse. Of rope construction only. Tied between two standard mainsheet horse eyes. 
3. Kicking strap. Shall not be attached to mast and boon other than to the standard fittings. Construction, type and power of purchase optional. 
4. Mainsheet outhaul system. Route, type and purchase optional. Clew slider around boon shall only be of rope. 
5. Mainsail cunningham system. Route, type and purchase optional. 
6. No rope or fittings shall inhibit or prevent the lowering of the mainsail while afloat. 
7. Jib sheets. Single 1-1 purchase only. Size and type of rope optional. No barber haulers or any other device to adjust jib sheet between jib clew and fairlead allowed. 
8. No rope or fittings shall inhibit or prevent the furling of the jib while afloat. 

32. SAILS. 

1. Only mainsail and jib shall be permitted. 
2. No sails, including replacements shall be permitted unless purchased when new from a Licensed Builder. All sails shall conform in all significant dimensions, to the pattern held by the designer. The measurements given in Rules 33 and 34 conform to these patterns. 
3. Recutting. Sails shall not be recut, resewn or altered other than for bona-fide repairs. Sails shall not be fitted with stiffening patches or additional cringles. 
4. Sail colour. All white only. 

33. MAINSAIL. 

1. Cringles. 

1. I.Shall not be more than 37mm in diameter.
2. II.Shall be fitted to clew so that its centre is not more than 30mm from the leech and foot edges of the sail. 
3. III.Shall be fitted to the tack so that its centre is not more than 30mm from the foot and 85mm from the extended luff line. 
4. IV.Shall be fitted to the leach for reefing not more than 710mm from the foot edge of the sail. 
5. V.Shall be fitted to the luff for reefing not more than 660mm from the foot edge of the sail. 

2. Cunningham block. Shall be fitted to the luff with its centre no less than 160mm from the foot edge of the sail.
3. Sail battens.

1. I.Three in numbers. Top batten length 500mm. Middle and bottom batten length 700mm. 
2. II. Sail batten position. Measured from the top front corner of the headboard in a straight line to the centre of the clew cringle. The centre of the batten pockets shall be 1325+/-10mm, 2605+/-10mm, 3910+/-10mm. 

4. Sail measurement conditions. The sail shall be dry, smoothed out on an approximately flat surface, with just sufficient tension on the fabric between measurement points to eliminate creases across the line of measurement. 
5. Mainsail luff measurement, Top forward corner of headboard to centre of tack cringle 4855+/-10mm. 
6. Mainsail foot measurement. Centre of tack cringle to centre of clew cringle 2210+/-10mm. 
7. Mainsail leach measurement. Centre of clew cringle to top forward corner of headboard 5210+/-10mm. 
8. Width measurements. Shall be taken as follows:- 

1. Half luff point. Shall be determined by folding so that the top forward corner of the headboard lies directly over the centre of the tack cringle, with the two halves of the luff coinciding. The fold so formed indicates the half luff point and shall be marked on the sail. 
2. II.Three-quarter luff point. Shall be determined by folding so that the top forward corner of the headboard lies directly over the nark made at the half luff point. (Rule 33.e.i). The fold so formed indicates the three-quarter luff point and shall be marked on the sail. 
3. III.Quarter luff point. Shall be determined by folding so that the centre of the tack cringle lies directly over the mark made at the half luff point (Rule 33.e.i), the fold so formed indicates the quarter luff points and shall be marked on the sail. 
4. IV.Half leech point. Shall be determined by folding so that the top forward corner of the headboard lies directly over the centre of the clew cringle. The fold so formed indicates the half leech point and shall be marked on the sail. 
5. Three-quarter leech point. Shall be determined by folding so that the top forward corner of the headboard lies directly over the mark made at the half leech point (Rule 33.e,iv). The fold so formed indicates the three-quarter leech point and shall be marked on the sail. 
6. VI.Quarter leech point, Shall be determined by folding so that the centre of the clew cringle lies directly over the mark made at the half leech point (Rule 33.e.iv), The fold so formed indicates the quarter leech point and shall be marked on the sail. 
7. VII.Width measurements shall be taken between luff and leech measurement points, over the full width of the sail. 
8. VIII.Width at quarter height. Maximum 2045mm. 
9. IX.Width at half height. Maximum 1570mm. 
10. Width at three-quarter height. Maximum 930mm. 

9. Headboard. Maximum top width 105mm. 
10. Roach. Maximum roach at centre batten measured from a straight line between top front corner of headboard and centre of clew cringle, 320mm.
11. Foot curvature. The foot curvature shall be measured from a straight line between the centres of the tack and clew cringles, at a right angle to the foot of the sail and shall be a maximum of 145mm.
12. Sail window. No sail window shall be permitted. 
13. Sail emblem. Shall be in accordance with the official plans. Shall be orange and fitted back to back on both sides of the sail. 
14. Sail numbers. Shall be fitted to both sides of sail either side of the sail seam between the bottom and middle battens. Shall be of the following dimensions. Height 300mm, width 200mm (except the number 1) and thickness 45mm.

34. JIB. 

1. Luff wire. The jib luff wire shall be measured from the bearing surfaces and shall be 3705+/-5mm. 
2. Luff measurement. Top forward corner of luff wire sleeve to bottom forward corner of luff wire sleeve 3650+/-10mm.
3. Foot measurement. Bottom forward corner of luff wire sleeve to centre of clew cringle 150+/-10mm. 
4. Leech measurement. Top forward corner of luff wire sleeve to centre of clew cringle 3380+/-10mm. 
5. Cringles. 

1. I.Clew cringle shall not be more than 37mm in diameter and its centre not more than 30mm from the leech and foot edges of the sail. 
2. II.Tack cringle shall not be more than 20mm in diameter and its centre not more than 20mm from the foot edge of the sail and 30mm from the luff edge of the sail. 
3. Sail window. Shall be of a shape and position as shown in diagram 5. 

35. BUOYANCY. 

1. Holes or openings into the buoyancy compartment shall not be permitted except as specified in Rules 13 and 17. 
2. Inspection hatch covers and drain plugs shall be secured in position when racing. 
3. Polystyrene foam buoyancy blocks totalling 5 cubic feet shall be installed between hull and deck mouldings. 

36. REPAIRS AND REPLACEMENTS. 

1. Repairs shall be permitted to damaged hulls, decks, centreboards, rudders, masts and booms, provided that such repairs do not alter shape or characteristics of the component so that its strength or performance is materially affected. 
2. Painting. Hull and deck nay be painted if necessary, 
3. Damaged fittings and fastenings. Replacement shall be permitted provided that the replacement fitting is positioned as close as practicable to the original. 

37. SPECIAL PROHIBITIONS, 

1. Ballast, whether in the boat or carried by the crew is prohibited. 
2. Any apparatus or contrivance extending outboard from the hull or spars, the purpose or effect of which may be to support or assist in supporting the helmsman outboard or partially outboard prohibited. 

38. CREW. 

1. Two people only shall normally be in the boat when racing. In races in which exception is made to this rule prior notice shall be published in the sailing instructions. 

DIAGRAMS